u-boot/fs/ext4/ext4fs.c
Stefan Brüns 66a47ff2d8 ext4: Allow reading files with non-zero offset, clamp read len
Support was already implemented, but not hooked up. This fixes several
fails in the test cases.

Signed-off-by: Stefan Brüns <stefan.bruens@rwth-aachen.de>
Acked-by: Stephen Warren <swarren@wwwdotorg.org>
2016-11-21 14:07:27 -05:00

245 lines
5.6 KiB
C

/*
* (C) Copyright 2011 - 2012 Samsung Electronics
* EXT4 filesystem implementation in Uboot by
* Uma Shankar <uma.shankar@samsung.com>
* Manjunatha C Achar <a.manjunatha@samsung.com>
*
* ext4ls and ext4load : Based on ext2 ls and load support in Uboot.
* Ext4 read optimization taken from Open-Moko
* Qi bootloader
*
* (C) Copyright 2004
* esd gmbh <www.esd-electronics.com>
* Reinhard Arlt <reinhard.arlt@esd-electronics.com>
*
* based on code from grub2 fs/ext2.c and fs/fshelp.c by
* GRUB -- GRand Unified Bootloader
* Copyright (C) 2003, 2004 Free Software Foundation, Inc.
*
* ext4write : Based on generic ext4 protocol.
*
* SPDX-License-Identifier: GPL-2.0+
*/
#include <common.h>
#include <ext_common.h>
#include <ext4fs.h>
#include "ext4_common.h"
#include <div64.h>
int ext4fs_symlinknest;
struct ext_filesystem ext_fs;
struct ext_filesystem *get_fs(void)
{
return &ext_fs;
}
void ext4fs_free_node(struct ext2fs_node *node, struct ext2fs_node *currroot)
{
if ((node != &ext4fs_root->diropen) && (node != currroot))
free(node);
}
/*
* Taken from openmoko-kernel mailing list: By Andy green
* Optimized read file API : collects and defers contiguous sector
* reads into one potentially more efficient larger sequential read action
*/
int ext4fs_read_file(struct ext2fs_node *node, loff_t pos,
loff_t len, char *buf, loff_t *actread)
{
struct ext_filesystem *fs = get_fs();
int i;
lbaint_t blockcnt;
int log2blksz = fs->dev_desc->log2blksz;
int log2_fs_blocksize = LOG2_BLOCK_SIZE(node->data) - log2blksz;
int blocksize = (1 << (log2_fs_blocksize + log2blksz));
unsigned int filesize = le32_to_cpu(node->inode.size);
lbaint_t previous_block_number = -1;
lbaint_t delayed_start = 0;
lbaint_t delayed_extent = 0;
lbaint_t delayed_skipfirst = 0;
lbaint_t delayed_next = 0;
char *delayed_buf = NULL;
short status;
/* Adjust len so it we can't read past the end of the file. */
if (len + pos > filesize)
len = (filesize - pos);
blockcnt = lldiv(((len + pos) + blocksize - 1), blocksize);
for (i = lldiv(pos, blocksize); i < blockcnt; i++) {
lbaint_t blknr;
int blockoff = pos - (blocksize * i);
int blockend = blocksize;
int skipfirst = 0;
blknr = read_allocated_block(&(node->inode), i);
if (blknr < 0)
return -1;
blknr = blknr << log2_fs_blocksize;
/* Last block. */
if (i == blockcnt - 1) {
blockend = (len + pos) - (blocksize * i);
/* The last portion is exactly blocksize. */
if (!blockend)
blockend = blocksize;
}
/* First block. */
if (i == lldiv(pos, blocksize)) {
skipfirst = blockoff;
blockend -= skipfirst;
}
if (blknr) {
int status;
if (previous_block_number != -1) {
if (delayed_next == blknr) {
delayed_extent += blockend;
delayed_next += blockend >> log2blksz;
} else { /* spill */
status = ext4fs_devread(delayed_start,
delayed_skipfirst,
delayed_extent,
delayed_buf);
if (status == 0)
return -1;
previous_block_number = blknr;
delayed_start = blknr;
delayed_extent = blockend;
delayed_skipfirst = skipfirst;
delayed_buf = buf;
delayed_next = blknr +
(blockend >> log2blksz);
}
} else {
previous_block_number = blknr;
delayed_start = blknr;
delayed_extent = blockend;
delayed_skipfirst = skipfirst;
delayed_buf = buf;
delayed_next = blknr +
(blockend >> log2blksz);
}
} else {
if (previous_block_number != -1) {
/* spill */
status = ext4fs_devread(delayed_start,
delayed_skipfirst,
delayed_extent,
delayed_buf);
if (status == 0)
return -1;
previous_block_number = -1;
}
memset(buf, 0, blocksize - skipfirst);
}
buf += blocksize - skipfirst;
}
if (previous_block_number != -1) {
/* spill */
status = ext4fs_devread(delayed_start,
delayed_skipfirst, delayed_extent,
delayed_buf);
if (status == 0)
return -1;
previous_block_number = -1;
}
*actread = len;
return 0;
}
int ext4fs_ls(const char *dirname)
{
struct ext2fs_node *dirnode;
int status;
if (dirname == NULL)
return 0;
status = ext4fs_find_file(dirname, &ext4fs_root->diropen, &dirnode,
FILETYPE_DIRECTORY);
if (status != 1) {
printf("** Can not find directory. **\n");
return 1;
}
ext4fs_iterate_dir(dirnode, NULL, NULL, NULL);
ext4fs_free_node(dirnode, &ext4fs_root->diropen);
return 0;
}
int ext4fs_exists(const char *filename)
{
loff_t file_len;
int ret;
ret = ext4fs_open(filename, &file_len);
return ret == 0;
}
int ext4fs_size(const char *filename, loff_t *size)
{
return ext4fs_open(filename, size);
}
int ext4fs_read(char *buf, loff_t offset, loff_t len, loff_t *actread)
{
if (ext4fs_root == NULL || ext4fs_file == NULL)
return -1;
return ext4fs_read_file(ext4fs_file, offset, len, buf, actread);
}
int ext4fs_probe(struct blk_desc *fs_dev_desc,
disk_partition_t *fs_partition)
{
ext4fs_set_blk_dev(fs_dev_desc, fs_partition);
if (!ext4fs_mount(fs_partition->size)) {
ext4fs_close();
return -1;
}
return 0;
}
int ext4_read_file(const char *filename, void *buf, loff_t offset, loff_t len,
loff_t *len_read)
{
loff_t file_len;
int ret;
ret = ext4fs_open(filename, &file_len);
if (ret < 0) {
printf("** File not found %s **\n", filename);
return -1;
}
if (len == 0)
len = file_len;
return ext4fs_read(buf, offset, len, len_read);
}
int ext4fs_uuid(char *uuid_str)
{
if (ext4fs_root == NULL)
return -1;
#ifdef CONFIG_LIB_UUID
uuid_bin_to_str((unsigned char *)ext4fs_root->sblock.unique_id,
uuid_str, UUID_STR_FORMAT_STD);
return 0;
#else
return -ENOSYS;
#endif
}